An electrical socket, also known as a power outlet or a switch socket, includes at least one output for receiving an electrical plug. Various wirings will be plugged into the electrical socket and connect to other circuits.
When the electrical socket and the electrical plug are mated, the electrical socket may have a locking function to prevent the electrical plug from detaching from the electrical socket. For example, pins of the electrical plug may insert into electrodes of the electrical socket and the electrodes press upon the pins to hold them to prevent the electrical plug from detaching from the electrical socket.
When the pins of the electrical plug are clamped by the electrodes, static friction is formed between the pins and the electrodes. Because the electrodes and the pins are both made of a metal material, the friction coefficient between the electrodes and the pins is small, so that it is hard to lock the pins over time. Furthermore, after the electrical socket has been used for a long time, the electrodes may be prone to wear out, thereby further reducing the locking effect of the electrical socket.